let allStudents = [];
let allGroups = [];
let groupOptionsLoaded = false;
let sPage = 1;
const S_PAGE_SIZE = 25;
let sSearchTimer = null;
let aSearchTimer = null;
let attachGroupLoaded = false;

async function loadGroupOptions(sel, selected) {
  if (!groupOptionsLoaded) {
    const res = await fetch(`${API}/api/groups`, { headers: hdr() });
    allGroups = await res.json();
    groupOptionsLoaded = true;
    const filt = document.getElementById('studentGroupFilter');
    if (filt && filt.options.length <= 1) {
      filt.innerHTML = `<option value="">Все группы</option>` +
        allGroups.map(g => `<option value="${g.id}">${esc(g.name)}</option>`).join('');
    }
  }
  if (sel) {
    sel.innerHTML = `<option value="">— не привязана —</option>` +
      allGroups.map(g => `<option value="${g.id}" ${selected == g.id ? 'selected' : ''}>${esc(g.name)}</option>`).join('');
  }
}

async function loadStudents() {
  const res = await fetch(`${API}/api/students`, { headers: hdr() });
  allStudents = await res.json();
  renderStudents();
}

function renderStudents() {
  const q = document.getElementById('studentSearch').value.trim().toLowerCase();
  const gid = document.getElementById('studentGroupFilter').value;
  let filtered = q ? allStudents.filter(s => s.name.toLowerCase().includes(q)) : allStudents;
  if (gid) filtered = filtered.filter(s => String(s.group_id) === gid);
  const totalPages = Math.max(1, Math.ceil(filtered.length / S_PAGE_SIZE));
  if (sPage > totalPages) sPage = 1;
  const slice = filtered.slice((sPage - 1) * S_PAGE_SIZE, sPage * S_PAGE_SIZE);
  const list = document.getElementById('studentList');
  if (!slice.length) { list.innerHTML = '<div style="color:var(--muted);text-align:center;padding:32px">Ничего не найдено</div>'; }
  else {
    list.innerHTML = slice.map(s => `
      <div class="item">
        <input class="name-input student-name-input" id="sname-${s.id}" value="${esc(s.name)}">
        <select class="group-select" id="sgroup-${s.id}"></select>
        <div class="student-actions">
          <button class="btn-save" data-save-student="${s.id}">Сохранить</button>
          <button class="btn-link" data-profile-student="${s.id}" title="Скачать профиль ученика (ZIP: фото и работы)">Профиль</button>
          <button class="btn-link" data-profile-data="${s.id}" title="Данные профиля: заполняют разделы страницы профиля в архиве">Данные</button>
          <button class="btn-link" data-export-student="${esc(s.name)}" title="Сформировать ZIP-отчёт: фотографии и файлы">Отчёт</button>
          <button class="btn-link" data-copy-student="${esc(s.name)}" title="Скопировать ссылку с подстановкой имени">Ссылка</button>
          <button class="btn-del" data-del-student="${s.id}" title="Удалить">&times;</button>
        </div>
      </div>
    `).join('');
    slice.forEach(s => loadGroupOptions(document.getElementById(`sgroup-${s.id}`), s.group_id));
  }
  renderPager(document.getElementById('pager'), sPage, totalPages, goStudentPage);
}

function goStudentPage(p) {
  sPage = p;
  renderStudents();
}

async function addStudent() {
  const input = document.getElementById('newStudent');
  const name = input.value.trim();
  if (!name) return;
  const res = await fetch(`${API}/api/students`, { method: 'POST', headers: hdrJson(), body: JSON.stringify({ name }) });
  if (res.ok) { input.value = ''; loadStudents(); fillAutocomplete(); showToast(`Добавлен: ${name}`); }
  else { const e = await res.json(); alert(e.error); }
}

async function saveStudent(id) {
  const name = document.getElementById(`sname-${id}`).value.trim();
  if (!name) return;
  const group_id = document.getElementById(`sgroup-${id}`).value;
  const res = await fetch(`${API}/api/students/${id}`, { method: 'PUT', headers: hdrJson(), body: JSON.stringify({ name, group_id }) });
  if (res.ok) { loadStudents(); fillAutocomplete(); showToast(`Сохранено: ${name}`); }
  else { const e = await res.json(); alert(e.error); }
}

let exportPendingName = null;

function openExportModal(name) {
  exportPendingName = name;
  document.getElementById('exportName').textContent = name;
  document.getElementById('exportForm').reset();
  document.getElementById('exportDateFrom').value = '';
  document.getElementById('expEntries').checked = true;
  document.getElementById('expPhotos').checked = true;
  document.getElementById('expCaptions').checked = true;
  document.getElementById('expFiles').checked = true;
  document.getElementById('expDates').checked = true;
  document.getElementById('exportModal').classList.add('open');
}

function closeExportModal() {
  document.getElementById('exportModal').classList.remove('open');
  exportPendingName = null;
}

function onExportPhotosToggle() {
  const on = document.getElementById('expPhotos').checked;
  document.getElementById('expCaptions').disabled = !on;
}

async function exportStudent(name, opts) {
  showToast(`Формируем отчёт: ${name}...`);
  try {
    const q = new URLSearchParams({ name });
    if (opts.dateFrom) q.set('date_from', opts.dateFrom);
    if (opts.dateTo) q.set('date_to', opts.dateTo);
    q.set('include_entries', opts.entries ? '1' : '0');
    q.set('include_photos', opts.photos ? '1' : '0');
    q.set('include_captions', opts.captions ? '1' : '0');
    q.set('include_files', opts.files ? '1' : '0');
    q.set('show_dates', opts.dates ? '1' : '0');
    const res = await fetch(`${API}/api/export/student?${q}`, { headers: hdr() });
    if (!res.ok) {
      const e = await res.json();
      alert(e.error || 'Не удалось сформировать отчёт');
      return;
    }
    const blob = await res.blob();
    downloadBlob(blob, `student_${safeWindowsName(name)}_report.zip`);
    showToast(`Готово: ${name}`);
  } catch (err) {
    alert('Ошибка при формировании отчёта');
  }
}

async function submitExport() {
  const name = exportPendingName;
  if (!name) return;
  const captionsEl = document.getElementById('expCaptions');
  const opts = {
    entries: document.getElementById('expEntries').checked,
    photos: document.getElementById('expPhotos').checked,
    files: document.getElementById('expFiles').checked,
    captions: captionsEl.checked && !captionsEl.disabled,
    dates: document.getElementById('expDates').checked,
    dateFrom: document.getElementById('exportDateFrom').value,
    dateTo: document.getElementById('exportDateTo').value,
  };
  if (!opts.entries && !opts.photos && !opts.files) {
    alert('Выберите хотя бы одну категорию: записи, фото или файлы');
    return;
  }
  if (opts.dateFrom && opts.dateTo && opts.dateFrom > opts.dateTo) {
    alert('Дата «С» позже даты «По»');
    return;
  }
  closeExportModal();
  await exportStudent(name, opts);
}

async function exportStudentProfile(id) {
  const s = allStudents.find(x => x.id === id);
  if (!s) return;
  const btn = document.querySelector(`[data-profile-student="${id}"]`);
  const label = btn ? btn.textContent : '';
  if (btn) { btn.disabled = true; btn.textContent = 'Готовим...'; }
  showToast(`Формируем профиль: ${s.name}...`);
  try {
    const res = await fetch(`${API}/api/export/student?name=${encodeURIComponent(s.name)}`, { headers: hdr() });
    if (!res.ok) {
      const e = await res.json().catch(() => ({}));
      showToast(e.error || 'Не удалось сформировать профиль');
      return;
    }
    const blob = await res.blob();
    downloadBlob(blob, `profile_${safeWindowsName(s.name)}_${new Date().toISOString().slice(0, 10)}.zip`);
    showToast(`Готово: ${s.name}`);
  } catch (err) {
    showToast('Ошибка при формировании профиля');
  } finally {
    if (btn) { btn.disabled = false; btn.textContent = label; }
  }
}

let profileDataId = null;
let profilePhotos = [];

function openProfileData(id) {
  profileDataId = id;
  loadGroupOptions();
  loadStudentPhotos(id);
  fetch(`${API}/api/students/${id}/profile`, { headers: hdr() })
    .then(r => (r.ok ? r.json() : Promise.reject(new Error('load'))))
    .then(data => fillProfileForm(data.profile, data.name, data.photo_path))
    .catch(() => fillProfileForm(null, '', ''));
  document.getElementById('profileDataModal').classList.add('open');
}

function closeProfileData() {
  document.getElementById('profileDataModal').classList.remove('open');
  profileDataId = null;
}

async function loadStudentPhotos(id) {
  try {
    const res = await fetch(`${API}/api/students/${id}/photos`, { headers: hdr() });
    if (!res.ok) return;
    const data = await res.json();
    profilePhotos = data.photos || [];
    document.getElementById('pfPhoto').value = data.photo_path || '';
    renderStudentPhotos();
  } catch (err) {
    profilePhotos = [];
  }
}

function renderStudentPhotos() {
  const wrap = document.getElementById('pfPhotos');
  if (!wrap) return;
  const main = document.getElementById('pfPhoto').value.trim();
  if (!profilePhotos.length) {
    wrap.innerHTML = '<span class="hint" style="margin:0">Пока нет загруженных фото</span>';
    return;
  }
  wrap.innerHTML = profilePhotos.map(p => `
    <div class="pf-photo${p.photo_path === main ? ' main' : ''}" data-pf-set="${p.id}" title="Сделать главным">
      <img src="${esc(p.photo_path)}" alt="" loading="lazy">
      ${p.photo_path === main ? '<span class="pf-badge">Главная</span>' : ''}
      <button type="button" class="pf-del" data-pf-del="${p.id}" title="Удалить фото">✕</button>
    </div>
  `).join('');
}

async function uploadStudentPhoto(file) {
  if (!profileDataId || !file) return;
  if (!file.type.startsWith('image/')) {
    alert('Можно загружать только изображения');
    return;
  }
  showToast('Загружаем фото...');
  const fd = new FormData();
  fd.append('photo', file);
  try {
    const res = await fetch(`${API}/api/students/${profileDataId}/photos`, { method: 'POST', headers: hdr(), body: fd });
    if (res.ok) {
      await loadStudentPhotos(profileDataId);
      showToast('Фото загружено');
    } else {
      const e = await res.json().catch(() => ({}));
      alert(e.error || 'Не удалось загрузить фото');
    }
  } catch (err) {
    alert('Ошибка при загрузке фото');
  }
}

async function setMainStudentPhoto(pid) {
  if (!profileDataId) return;
  try {
    const res = await fetch(`${API}/api/students/${profileDataId}/photos/${pid}/main`, { method: 'PUT', headers: hdr() });
    if (res.ok) {
      const r = await res.json();
      document.getElementById('pfPhoto').value = r.photo_path || '';
      renderStudentPhotos();
      showToast('Главное фото обновлено');
    } else {
      const e = await res.json().catch(() => ({}));
      alert(e.error || 'Не удалось выбрать главное фото');
    }
  } catch (err) {
    alert('Ошибка при выборе главного фото');
  }
}

async function delStudentPhoto(pid) {
  if (!profileDataId) return;
  if (!confirm('Удалить это фото?')) return;
  try {
    const res = await fetch(`${API}/api/students/${profileDataId}/photos/${pid}`, { method: 'DELETE', headers: hdr() });
    if (res.ok) {
      await loadStudentPhotos(profileDataId);
      showToast('Фото удалено');
    } else {
      const e = await res.json().catch(() => ({}));
      alert(e.error || 'Не удалось удалить фото');
    }
  } catch (err) {
    alert('Ошибка при удалении фото');
  }
}

function fillProfileForm(profile, name, photoPath) {
  const p = profile || {};
  const set = (id, v) => { document.getElementById(id).value = v === null || v === undefined ? '' : String(v); };
  document.getElementById('profileDataTitle').textContent = name || 'Профиль ученика';
  set('pfRole', p.role); set('pfStatus', p.status); set('pfStatusNote', p.status_note);
  set('pfCity', p.city); set('pfMentor', p.mentor); set('pfJoined', p.joined);
  set('pfBio', p.bio); set('pfQuote', p.quote);
  set('pfTags', (p.tags || []).join(', '));
  set('pfContacts', (p.contacts || []).map(c => [c.icon || 'link', c.label, c.href || ''].join(' | ')).join('\n'));
  set('pfAchievements', (p.achievements || []).join('\n'));
  set('pfSkills', (p.skills || []).map(s => [s.group || 'Навыки', s.name, s.level || '', s.value === null || s.value === undefined ? '' : s.value].join(' | ')).join('\n'));
  set('pfExperience', (p.experience || []).map(e => [e.title, e.company || '', e.period || '', e.date || '', e.badge || '', e.description || '', (e.tags || []).join(',')].join(' | ')).join('\n'));
  set('pfEducation', (p.education || []).map(m => [m.module, m.progress === null || m.progress === undefined ? '' : m.progress, m.grade || '', m.teacher || ''].join(' | ')).join('\n'));
  set('pfPhoto', photoPath || '');
}

function collectProfile() {
  const val = id => document.getElementById(id).value.trim();
  const lines = id => val(id).split('\n').map(s => s.trim()).filter(Boolean);
  const cols = line => line.split('|').map(s => s.trim());
  const intOrNull = s => (s === '' || s === null || s === undefined ? null : Number(s));
  const out = {
    role: val('pfRole') || null,
    status: val('pfStatus') || null,
    status_note: val('pfStatusNote') || null,
    city: val('pfCity') || null,
    mentor: val('pfMentor') || null,
    joined: val('pfJoined') || null,
    bio: val('pfBio') || null,
    quote: val('pfQuote') || null,
    tags: val('pfTags') ? val('pfTags').split(',').map(s => s.trim()).filter(Boolean) : [],
    contacts: lines('pfContacts').map(l => {
      const c = cols(l);
      return { icon: c[0] || 'link', label: c[1] || '', href: c[2] || '' };
    }).filter(c => c.label),
    achievements: lines('pfAchievements'),
    skills: lines('pfSkills').map(l => {
      const c = cols(l);
      return { group: c[0] || 'Навыки', name: c[1] || '', level: c[2] || null, value: intOrNull(c[3]) };
    }).filter(s => s.name),
    experience: lines('pfExperience').map(l => {
      const c = cols(l);
      return {
        title: c[0] || '', company: c[1] || null, period: c[2] || null, date: c[3] || null,
        badge: c[4] || null, description: c[5] || null,
        tags: c[6] ? c[6].split(',').map(s => s.trim()).filter(Boolean) : [],
      };
    }).filter(e => e.title),
    education: lines('pfEducation').map(l => {
      const c = cols(l);
      return { module: c[0] || '', progress: intOrNull(c[1]), grade: c[2] || null, teacher: c[3] || null };
    }).filter(m => m.module),
  };
  const hasData = Object.keys(out).some(k => (Array.isArray(out[k]) ? out[k].length : out[k]));
  return hasData ? out : null;
}

async function saveProfileData(e) {
  e.preventDefault();
  if (!profileDataId) return;
  const body = { profile: collectProfile() };
  const photoPath = document.getElementById('pfPhoto').value.trim();
  body.photo_path = photoPath || null;
  const res = await fetch(`${API}/api/students/${profileDataId}/profile`, {
    method: 'PUT',
    headers: hdrJson(),
    body: JSON.stringify(body),
  });
  if (res.ok) {
    closeProfileData();
    loadStudents();
    showToast('Данные профиля сохранены');
  } else {
    const err = await res.json().catch(() => ({}));
    alert(err.error || 'Не удалось сохранить данные профиля');
  }
}

async function delStudent(id) {
  if (!confirm('Удалить ученика из списка? Старые записи останутся.')) return;
  await fetch(`${API}/api/students/${id}`, { method: 'DELETE', headers: hdr() });
  loadStudents();
  fillAutocomplete();
}

function openBatchAdd() {
  document.getElementById('batchText').value = '';
  loadGroupOptions(document.getElementById('batchGroup'), '');
  document.getElementById('batchModal').classList.add('open');
}

function closeBatchAdd() {
  document.getElementById('batchModal').classList.remove('open');
}

async function batchAdd() {
  const raw = document.getElementById('batchText').value;
  const names = [...new Set(raw.split('\n').map(s => s.trim()).filter(Boolean))];
  if (!names.length) return;
  const group_id = document.getElementById('batchGroup').value;
  let added = 0, dupes = 0;
  for (const name of names) {
    const res = await fetch(`${API}/api/students`, { method: 'POST', headers: hdrJson(), body: JSON.stringify({ name, group_id: group_id || null }) });
    if (res.ok) added++;
    else if (res.status === 409) dupes++;
  }
  closeBatchAdd();
  loadStudents();
  fillAutocomplete();
  showToast(`Добавлено: ${added}${dupes ? `, дубликатов: ${dupes}` : ''}`);
}

document.getElementById('newStudent').addEventListener('keydown', e => { if (e.key === 'Enter') addStudent(); });
document.getElementById('batchForm').addEventListener('submit', e => {
  e.preventDefault();
  batchAdd();
});
document.getElementById('studentSearch').addEventListener('input', () => {
  clearTimeout(sSearchTimer);
  sSearchTimer = setTimeout(() => { sPage = 1; renderStudents(); }, 300);
});
document.getElementById('studentGroupFilter').addEventListener('change', () => { sPage = 1; renderStudents(); });

function exportStudentsCSV() {
  const gid = document.getElementById('studentGroupFilter').value;
  const list = gid ? allStudents.filter(s => String(s.group_id) === gid) : allStudents;
  if (!list.length) { alert('Нет данных для экспорта'); return; }
  const rows = [['Фамилия Имя', 'Группа', 'Ссылка на страницу']];
  list.forEach(s => {
    rows.push([
      s.name,
      s.group_name || '',
      `${location.origin}/?nameInput=${encodeURIComponent(s.name)}`
    ]);
  });
  const csv = rows.map(r => r.map(c => `"${String(c).replace(/"/g, '""')}"`).join(';')).join('\n');
  const blob = new Blob(['\uFEFF' + csv], { type: 'text/csv;charset=utf-8' });
  const url = URL.createObjectURL(blob);
  const a = document.createElement('a');
  a.href = url;
  const groupName = gid ? (allGroups.find(g => g.id == gid)?.name || 'group') : 'all';
  a.download = `students_${groupName.replace(/[\\/:*?"<>|]/g, '_')}.csv`;
  a.click();
  URL.revokeObjectURL(url);
  showToast(`Экспортировано: ${list.length}`);
}

async function exportStudentsUrls() {
  const gid = document.getElementById('studentGroupFilter').value;
  const list = gid ? allStudents.filter(s => String(s.group_id) === gid) : allStudents;
  if (!list.length) { alert('Нет данных для экспорта'); return; }
  const groupName = gid ? (allGroups.find(g => g.id == gid)?.name || 'group') : 'all';
  await exportStudentUrlZip(list, `students_${groupName.replace(/[\\/:*?"<>|]/g, '_')}.zip`);
  showToast(`Экспортировано: ${list.length}`);
}

async function openBatchAttach() {
  const sel = document.getElementById('attachGroup');
  if (!attachGroupLoaded) {
    const res = await fetch(`${API}/api/groups`, { headers: hdr() });
    const groups = await res.json();
    sel.innerHTML = `<option value="">— выберите группу —</option>` +
      groups.map(g => `<option value="${g.id}">${esc(g.name)}</option>`).join('');
    attachGroupLoaded = true;
  }
  document.getElementById('attachSearch').value = '';
  renderAttachList();
  document.getElementById('attachModal').classList.add('open');
}

function closeBatchAttach() {
  document.getElementById('attachModal').classList.remove('open');
}

function renderAttachList() {
  const q = document.getElementById('attachSearch').value.trim().toLowerCase();
  const filtered = q ? allStudents.filter(s => s.name.toLowerCase().includes(q)) : allStudents;
  const list = document.getElementById('attachList');
  if (!filtered.length) { list.innerHTML = '<div style="color:var(--muted);text-align:center;padding:16px">Никого не найдено</div>'; return; }
  list.innerHTML = filtered.map(s => `
    <label>
      <input type="checkbox" value="${s.id}">
      <span>${esc(s.name)}</span>
      <span class="cur">${s.group_name ? esc(s.group_name) : ''}</span>
    </label>
  `).join('');
}

async function batchAttach() {
  const group_id = document.getElementById('attachGroup').value;
  const ids = [...document.querySelectorAll('#attachList input[type=checkbox]:checked')].map(c => c.value);
  if (!group_id) { alert('Выберите группу'); return; }
  if (!ids.length) { alert('Выберите учеников'); return; }
  const res = await fetch(`${API}/api/students/batch-group`, {
    method: 'POST',
    headers: hdrJson(),
    body: JSON.stringify({ group_id, student_ids: ids })
  });
  if (res.ok) {
    const r = await res.json();
    closeBatchAttach();
    loadStudents();
    showToast(`Прикреплено: ${r.updated}`);
  } else { const e = await res.json(); alert(e.error); }
}

document.getElementById('attachForm').addEventListener('submit', e => {
  e.preventDefault();
  batchAttach();
});
document.getElementById('attachSearch').addEventListener('input', () => {
  clearTimeout(aSearchTimer);
  aSearchTimer = setTimeout(renderAttachList, 300);
});

document.getElementById('exportForm').addEventListener('submit', e => {
  e.preventDefault();
  submitExport();
});
document.getElementById('exportCancelBtn').addEventListener('click', closeExportModal);
document.getElementById('expPhotos').addEventListener('change', onExportPhotosToggle);
document.getElementById('exportModal').addEventListener('click', e => { if (e.target === e.currentTarget) closeExportModal(); });

document.getElementById('addStudentBtn').addEventListener('click', addStudent);
document.getElementById('batchAddBtn').addEventListener('click', openBatchAdd);
document.getElementById('batchAttachBtn').addEventListener('click', openBatchAttach);
document.getElementById('exportStudentsCsvBtn').addEventListener('click', exportStudentsCSV);
document.getElementById('exportStudentsUrlsBtn').addEventListener('click', exportStudentsUrls);
document.getElementById('batchModal').addEventListener('click', e => { if (e.target === e.currentTarget) closeBatchAdd(); });
document.getElementById('attachModal').addEventListener('click', e => { if (e.target === e.currentTarget) closeBatchAttach(); });
document.getElementById('batchCancelBtn').addEventListener('click', closeBatchAdd);
document.getElementById('attachCancelBtn').addEventListener('click', closeBatchAttach);

document.getElementById('studentList').addEventListener('click', e => {
  const sv = e.target.closest('[data-save-student]');
  if (sv) { saveStudent(parseInt(sv.dataset.saveStudent, 10)); return; }
  const cp = e.target.closest('[data-copy-student]');
  if (cp) { copyStudentLink(cp.dataset.copyStudent); return; }
  const ex = e.target.closest('[data-export-student]');
  if (ex) { openExportModal(ex.dataset.exportStudent.trim()); return; }
  const pf = e.target.closest('[data-profile-student]');
  if (pf) { exportStudentProfile(parseInt(pf.dataset.profileStudent, 10)); return; }
  const pd = e.target.closest('[data-profile-data]');
  if (pd) { openProfileData(parseInt(pd.dataset.profileData, 10)); return; }
  const dl = e.target.closest('[data-del-student]');
  if (dl) { delStudent(parseInt(dl.dataset.delStudent, 10)); }
});

document.getElementById('profileDataForm').addEventListener('submit', saveProfileData);
document.getElementById('profileDataCancelBtn').addEventListener('click', closeProfileData);
document.getElementById('pfPhotoUploadBtn').addEventListener('click', () => document.getElementById('pfPhotoFile').click());
document.getElementById('pfPhotoFile').addEventListener('change', e => {
  const f = e.target.files && e.target.files[0];
  e.target.value = '';
  if (f) uploadStudentPhoto(f);
});
document.getElementById('pfPhotos').addEventListener('click', e => {
  const del = e.target.closest('[data-pf-del]');
  if (del) { delStudentPhoto(parseInt(del.dataset.pfDel, 10)); return; }
  const set = e.target.closest('[data-pf-set]');
  if (set) setMainStudentPhoto(parseInt(set.dataset.pfSet, 10));
});
document.addEventListener('paste', e => {
  if (!profileDataId) return;
  if (!document.getElementById('profileDataModal').classList.contains('open')) return;
  const items = e.clipboardData && e.clipboardData.items;
  if (!items) return;
  for (const it of items) {
    if (it.type && it.type.startsWith('image/')) {
      const f = it.getAsFile();
      if (f) {
        e.preventDefault();
        uploadStudentPhoto(f);
      }
      return;
    }
  }
});
document.getElementById('profileDataModal').addEventListener('click', e => { if (e.target === e.currentTarget) closeProfileData(); });

(async () => {
  if (await checkAuth()) {
    buildSidebar(document.body.dataset.page);
    fillAutocomplete();
    loadGroupOptions();
    loadStudents();
  }
})();